Date:	Tue, 26 Jun 2001 16:27:54 +0300 (IDT)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To:	djgpp AT delorie DOT com
Subject:	Re: DJGPP reserves wrong int size
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On Tue, 26 Jun 2001, Graaagh the Mighty wrote:

> >The purpose of that is to keep the stack aligned to a 32 byte
> >boundary, which improves performance on today's high-end processors.
> 
> Modern processors care about alignments as large as *256 bits*!? 64
> bits for doubles or for ints on 64 bit chips, I figured, but 256!?

It's all in the Intel manuals; please read them.  Due to various data
prefetch penalties, they recommend that the stack be aligned on
16-byte boundary.  I didn't analyze the code produced by GCC too
deeply, but it might be considering the possibility that the stack
frame is only aligned initially to 4 bytes, since greater alignment is
normally not guaranteed, especially if you mix code produced by
different compilers.

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